Graphical elements with 'Displayed=FALSE' changes position in treeview.

Testing:

- Open a any graphical block.  (Select from teh library and click 'Home/Open block')

- Select the block from the tree view, and click 'Show/Graphical sub-elements'

- Expand the properties of the first graphical sub-element, and uncheck the 'Displayed' property.

- If the element remains at its position in the tree view (and is not moved at the end of teh list of sub-elements), than it works.